Food

A Food Borne Illness That Deserves More Attention: Listeriosis

The first reports of a food borne illness outbreak from hot dogs and deli meats started to accumulate in summer 1998. Officials could not have guessed that the effort to contain the eruption from an organism causing illnesses and deaths would be so ineffective that they would still be counting victims in 1999. Unlike Salmonella and E. Coli, Listeria is not a household word in the United States.

There are only 1000 to 2000 cases of Listeriosis reported annually in the United States. It is very troubling that the percentage of people who die from the illness is much higher than from most other food borne illness-causing microorganisms. Listeria monocytogenes – the bacteria that causes Listeriosis, is rare but in some cases, is catastrophic. The incubation period can be very long, from 1 up to 70 days before symptoms appear. Symptoms include nausea, vomiting, headache, fever, chills, backache (common flu-like symptoms in healthy individuals) and meningitis. For pregnant women, it can cause miscarriages and stillbirth. Listeria is carried in the intestines of animals and can easily come in contact with dairy products, uncooked meats, fish, poultry and vegetables as well as precooked deli meats like the ones responsible for the August 1998 Listeria outbreak. Unlike many other disease-causing bacteria, Listeria can grow in a refrigerator kept at a temperature of 40°F, which means leftovers should be reheated to kill any bacteria that grow during cold storage.

American scientists began to take Listeriosis seriously in 1985, when eighteen deaths were traced to the eating of soft cheese from a now defunct company. There were thirty stillbirths and deaths of newborns. Another one hundred and forty two became ill. Listeriosis is more troubling today for several reasons, including changes in the makeup of the population and the increasingly complex way food is processed and distributed. The population is aging in the United States and the contaminated products from the involved plant are distributed all over the United States.

It is strongly urged that those at the greatest risk from Listeria (pregnant women, very young, very old, and people with compromised immune systems) to stay away from all soft cheeses and to cook all products well. It is essential to cook hot dogs until the internal temperature reaches 165°F, by either frying or steaming. Cooking in the microwave oven is not recommended due to uneven distribution of heat.

But what about the deli meats? Unless people at high risk are willing to eat salami, corned beef, and pastrami "hot" in other words, they should not eat these products.

Please call the Bureau of Consumer Health Services at 713-794-9200 for more information about Listeriosis, or any other food-safety related topic.

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